Background: To externally validate and assess the robustness of two nomograms to predict the recurrence risk of women with endometrial cancer (EC).
Methods: Using an independent, multicentre external patient cohort we assessed the discrimination and calibration of two nomograms--the 3-year isolated loco-regional (ILRR) and distant (DR) recurrence nomograms--in women with surgically treated stage I-III EC.
Results: Two hundred and seventy one eligible women were identified from two university hospital databases and the Senti-Endo trial. The median follow-up and initial recurrence time were 38.1 (range: 12-69) and 22.0 (range: 8.3-55) months, respectively. The overall recurrence rate was 13.8% (37 out of 271). Predictive accuracy according to the discrimination was 0.69 (95% CI, 0.58-0.79) and 0.66 (95% CI, 0.60-0.71) for the 3-year ILRR and DR nomograms, respectively. The correspondence between observed recurrence rate and the nomogram predictions suggests a moderate calibration of the nomograms in the validation cohort.
Conclusion: The nomograms were externally validated and shown to be partly generalisable to a new and independent patient population. The tools need to be improved by including information on the lymph node status and adjuvant therapies.